The emergence of antibiotic resistance in bacteria has severe medical consequences. The goal of the proposed work is to evaluate the use of catalytic antibodies for blocking cell wall biosynthesis in vancomycin resistant bacteria. These resistant bacteria synthesize a modified cell wall substrate with a terminal D-ala-D-lac. This proposal outlines a strategy to construct a phage displayed library of scFv antibodies and then select specific antibodies that catalyze the cleavage the ester linkage of D-ala-D-lac. These antibodies will be tested for their ability to block cell wall biosynthesis using a standard microdilution broth assay. In addition, antibodies which bind D-ala-D-lac will also be selected from the phage library and tested in the microdilution broth assay. Comparison of the two types of antibodies should be useful in evaluating the advantages of catalysis versus binding for inhibiting biochemical processes.